1. Related Applications
This application claims priority to Switzerland Application No. 2009/CH0088, filed Jan. 21, 2009, which is hereby incorporated in its entirety by reference.
2. Field of the Invention 
The invention relates to a chronograph according to the independent claim. Advantageous embodiments arise from the subclaims.
3. Background of the Related Art
The relevant state of the art comprises in particular chronographs that have a rattrapante function. In this case, the rattrapante mechanism is mostly used for intermittently stopping the chronograph hand during the time measurement, whilst the measuring process is still running, and then to have it jump forwards to the total measured time. This is for instance the case in order to allow the elapsed time to that point (split time) to be read easily whilst the total elapsed time still continues being recorded.
Such a chronograph with only one rattrapante hand is known from DE4209580A1. In this known chronograph, after starting, the chronograph hand and the rattrapante hand can be stopped again together by activating a first actuator. It is also possible with a second actuator to stop only the rattrapante hand whilst the chronograph hand continues to run. This allows split times within a minute to be measured. When the second actuator is activated again, the rattrapante hand jumps to the position of the running chronograph hand and continues to run together with it, being ready for a renewed measuring of a split time. Measuring split times is possible as often as desired but the last measured split time is always lost. If one also wishes to stop the chronograph hand, the first actuator needs to be activated. There are thus two states of the standing hand. Either both hands are one above the other or each hand has its own position. This means that only two times are continuously visible through the position of the standing hands.
DE1673837 concerns a stopwatch provided with a rattrapante in which the rattrapante is borne by a pin passing through a tube and is supported by an elastically stressed hammer and a heart.
EP1584997 refers to a chronograph with a movement whose seconds' chronograph hand and, in a number especially of thirty steps per rotation, whose minutes' chronograph hand can be driven in rotation, with a control device for stopping the seconds' chronograph hand and the minutes' chronograph hand that has a trigger element for starting and stopping the seconds' chronograph hand and of the minutes' flyback hand.
EP1491972A1 pertains to a watch, in particular a wristwatch, with an analog time display that has at least a minutes' hand and an hours' hand. The watch is further provided with a rattrapante mechanism having at least a minutes' rattrapante hand and/or hours' rattrapante hand placed coaxially to the hands of the normal time display. In a normal mode of the watch, the rattrapante hand or hands are moved synchronously with the hands of the time display and in superposed position relative thereto, while in a time-measuring mode it/they can be halted to mark any point in time and be brought back afterwards with the hands of the normal time display to an superposed position relative thereto. The frictional coupling of the rattrapante mechanism is preferably arranged non-coaxially to the axis of the watch's motion train.
DE10135110A1 relates to a chronograph having a chronograph gear through which, when a first actuator is manually activated, a chronograph hand staff of a chronograph can be driven in rotation, and having also, coaxially to the chronograph hand staff, a rattrapante hand staff of a rattrapante hand that can be driven in superposed fashion with the chronograph hand. There is on the chronograph hand staff a seconds' heart for resetting the chronograph hand, the chronograph hand staff and the rattrapante hand staff being connected in locked-rotation to one another through a rattrapante heart cam with a frictional coupling. On the rattrapante hand staff, there is a rattrapante wheel that can be hugged by the gripper arms of a rattrapante gripper while under spring preload and whose rotation can be blocked through friction-locking or form-fitting. Furthermore, there is a switch element that is moved by manually activating a second actuator between a locked position and a released position and that allows the gripper arms to be moved removably from their rotation movement by the rattrapante hand.